Working at Kaikarou in the red-light district of Edo Yoshiwara, Ikutarou finds himself among many beautiful women. One in particular, Fuyou, seems to have been gifted with not only beauty but intelligence as well. An intelligence that people from many walks of life secretly turn to when they cannot go to the police. After discovering this secret, Ikutarou is made to be Fuyou's "feet," made to go out to observe crime scenes and evidence to report back to Fuyou so that she may solve the case even while being forbidden from leaving Kaikarou. Will this impromptu partnership work out? Will Fuyou be able to solve the case?